Patentee Failed to Rebut Presumption that Doctrine of Equivalents was Unavailable

A G Design & Associates LLC, v. Trainman Lantern Company, Inc., [2007-1481 ](March 24, 2008)[PROST, Rader, Schall] NON-PRECEDENTIAL The Federal Circuit vacated and remanded a preliminary injunction against TLC's infringement of U.S. Patent No. 7,118,245 on a trainman’s lantern.
BRIEF: The Federal Circuit reviews a grant of a preliminary injunction for an abuse of discretion. An abuse of discretion may be established by showing that the court made a clear error of judgment in weighing relevant factors or exercised its discretion based upon an error of law or clearly erroneous factual findings. The Federal Circuit found that prosecution history estoppel likely precludes a finding of infringement under the doctrine of equivalents in the present case, and thus it did not have to decide whether the district court’s application of the doctrine of equivalents was otherwise correct.
The Federal Circuit noted that in response to a rejection based on prior art during prosecution, AG made a narrowing amendment adding several claim limitations to claim one of the ’245 patent, including "a plurality of ports" formed in the reflector. Accordingly, equivalents are presumptively not available with respect to the limitation of "a plurality of ports" formed in the reflector. AG argued that the amendment in question was only tangentially related to the equivalent in question. The Federal Circuit said that this argument conflated Festo prosecution history estoppel tangential rebuttal analysis with the doctrine of equivalents function-way-result test. In our view, the relevant equivalent in question is the accused device’s reflector without a plurality of ports.